Types of cracks in building varies with the type of building and construction. Cracks are always a hint of the stability and strength of the structure. Here we are going to find out the main causes and the remedial measures to tackle each of them.
Main causes of different types of cracks in building details
There are different types of cracks in building depending on the causes. Let’s jump right into one at a time.
- This is a common cause of cracks in building.
- Thermal movement is the expansion and contraction with changes in temperature regardless of the structure’s cross-sectional area.
Preventive Measures for thermal movement
- There are chances of chemical reactions to occur because of the materials used to build the concrete or materials.
- Cracks might develop in concrete periodically as the result of developing expansive reactions between aggregate having active silica and alkalis from cement hydration, admixtures or external sources.
Preventive Measures for the types of cracks in building
- Majority of the building materials expand when they absorb moisture from the atmosphere and shrink when they become dry.
- In this type of cracks in the building, the main causes of cracks are the excess water. The amount of water needed in the mortar mix causes shrinkage.
- Shrinkage cracks may also be due to heat of hydration and lack of curing.
4. Types of cracks generated due to quantity of Cement
The proportion should be such that the cement in the mix is optimum. Higher the cement, greater the shrinkage/drying.
Do not use excessive cement in the mortar mix.
Crack happens because of the rapid shift in lower layer of the earth.
Build the foundation of building on firm ground. Tie up the building at base level, door level and roof level with connecting beams.
We covered the first five types of cracks in building. Good to have you here. Let’s move on to the remaining.
- Due to the expansive action of root growing under the base, fast growing trees may often cause cracks in walls in the area around the walls.
- Also, due to moisture contained by roots, cracks occur in clay soil.
Preventive Measures for the types of cracks in building
Do not plant trees too close to the house. If they start growing in or near walls, remove any saplings from the trees as quickly as possible.
7. Bad construction practices that cause some types of cracks in building
- Owing to indifference, carelessness, greed or incompetence, there is a general lack of good building practices
- It is certainly vital for the building agency and the owner to ensure high quality material selection and good construction practices for a safe building.
At the time of construction, careful inspection and use of materials of high quality is required.
8. Corrosion Cracks
- The pH level of the concrete under normal conditions is high (above 12.5).
- The high concrete pH allows for the formation of an inactive layer of ferric oxide around the reinforcement, avoiding corrosion.
- The reinforced steel has two important causes of corrosion:
- Chloride penetration
- Penetration of chloride decreases the concrete’s pH level as oxygen, chlorides, and moisture both enter the concrete.
As per IS 456-2000, use acceptable covers. When mixing concrete, use potable water.
9. Types of cracks in building due to elastic deformation
- In different sections, unevenly loaded walls experience enormous variations in stress that cause cracks in walls.
- Different shear stresses in these materials result in cracks at the junction when two building materials like masonry, concrete, steel, etc.
- with broadly different elastic properties are constructed together under the impact of load.
- In a building’s structural elements, dead and living loads cause elastic deformation.
- The amount of deformation depends significantly on the material’s elastic modulus, the loading magnitude and the component dimensions.
10. Foundation movement and settlement of soil
- Shear cracks occur in the base due to enormous differential settlement. Structures built on expansive soils that are susceptible to swelling due to changes in soil moisture content are highly susceptible to cracking when absorbing moisture and shrinking when drying.
11. Permeability of concrete
- The process of corrosion in concrete begins with the penetration of many aggressive agents and is a significant cause of wall cracks.
- Essentially, the ability of concrete to withstand weathering action, chemical attack or some other degradation mechanism is dictated.
- Low permeability is thus the primary factor in concrete resilience.
- Concrete permeability, water-cement ratio, curing, air voids due to poor compaction, use of admixtures, micro-cracks due to loading, cyclic exposure to thermal variations, and concrete ageing are influenced by several factors.
- Cement mixture permeability is a feature of the water-cement ratio due to high-quality materials, sufficient proportioning, and good construction practice.
- Concrete permeability is a direct result of the interconnection and porosity of the cement paste pores.
12. Poor Workmanship
- The lower mixing of building materials such as sand, cement and concrete, creates cracks on walls, slabs, beams, etc.
- Bad workmanship typically results from a lack of proper oversight, incompetence, neglect, and many others, or a mixture of all of these.
13. Lack Of Maintenance
- It is necessary to take good care of your home at all times, and this can be achieved by doing routine maintenance work.
- This means the foundation of the building remains intact and it also contributes to its lifetime.
Time to meet the last cause. Its the structural design of the structure.
14. Types of cracks due to structural design
- Poor or bad structural design and specifications are another striking causes of the cracks in buildings made of majorly concrete.
- The designer needs to consider all the environmental aspects which include soil investigations, this will enable the designer to come up with a properly robust design of the foundation.
In nutshell, each type of cracks have to be analysed and proper treatment methods and retrofits have to be adopted to restore the structure to last long.
Hope the article could educate you on the types of cracks in building, the main causes and preventive measures. Let me know if you have any doubts in the comments.